Oregon Revised Statutes Crimes and Punishments § 165.027

(1) In any prosecution for forgery of a bank bill or note or for criminal possession of a forged bank bill or note, the testimony of any person acquainted with the signature of the officer or agent authorized to sign the bills or notes of the bank of which such bill or note is alleged to be a forgery, or who has knowledge of the difference in appearance of the true and forged bills or notes thereof, may be admitted to prove that it is a forgery.

(2) In any prosecution for forgery or for criminal possession of any note, certificate, bond, bill of credit, or other security or evidence of debt issued on behalf of the United States or any state or territory, the certificate duly sworn to of the Secretary of the Treasury, or of the Treasurer of the United States, or of the secretary or treasurer of any state or treasury on whose behalf the note, certificate, bond, bill of credit or other security or evidence of debt purports to have been issued, shall be admitted as evidence to prove that it is a forgery.